A number of methods have been conventionally proposed for the purpose of obtaining a high-strength concrete formed body.
For example, PTL 1 describes a concrete placing method which is characterized by constructing a formwork with a shuttering having a dehydrating/deaerating sheet stuck onto a surface of a sheathing board, placing a concrete within the formwork of the shuttering such that the dehydrating/deaerating sheet-stuck surface is arranged inward, and then forming a reduced pressure state in the inside of the dehydrating/deaerating sheet.
In addition, for example, PTL 2 describes a vacuum deaeration treatment method of a lightweight foamed concrete by putting a mortar foamed body in a closed vessel and reducing the pressure to not more than a saturated steam pressure at a temperature of the foamed body, thereby evaporating the moisture, before the mortar foamed body is subjected to high-pressure steam curing to produce a lightweight foamed concrete, which is characterized by setting up an end point of the vacuum deaeration treatment while making the amount of moisture evaporated from the foamed body as a barometer.